You have to check Daily Trip Coverage for the date and category you're interested in. If you want historical data you can check the ALPA site, under I think the Scheduling Committee tab. They put out a report that shows the # of GS by category/month. Keep in mind that its probably been slow since last summer and is only really ramping up the past few weeks. Can't hurt to put it in and see what happens.

Out of Base GS are pretty low on the totem pole, but there have been a few this weekend in various categories. They will go out before an IA which have also been awarded recently. Don't tell your wife it's an option or she'll log on and sign you up when you're not looking!